What does a 'bel' measure?

A 'bel' is a unit of measurement used to express the logarithmic ratio of two power levels, often specifically referring to signal strength in telecommunications and audio. It is named after Alexander Graham Bell and serves as a means to quantify sound intensity or electrical signal levels. In the context of telecommunications, a 'bel' measures how much stronger one signal is compared to another, allowing professionals to determine the quality and effectiveness of signal transmission in systems.

The application of the 'bel' in measuring signal strength is vital in ensuring that communications systems maintain adequate performance levels, determine interference, and assess overall network health. Thus, saying that a 'bel' measures signal strength captures its fundamental role in evaluating and comparing power levels in various systems.